Newsgroups: comp.robotics
Path: brunix!uunet!cs.utexas.edu!csc.ti.com!tilde.csc.ti.com!mksol!strohm
From: strohm@mksol.dseg.ti.com (john r strohm)
Subject: Re: Laser rangefinder (was:  IR rangefinder source)
Message-ID: <1993Apr8.231214.21663@mksol.dseg.ti.com>
Organization: Texas Instruments, Inc
References: <DAC.93Apr8150723@locust.frc.ri.cmu.edu> <HABA.93Apr9004233@lesti.hut.fi>
Distribution: comp
Date: Thu, 8 Apr 1993 23:12:14 GMT
Lines: 20

In article <HABA.93Apr9004233@lesti.hut.fi> haba@lesti.hut.fi (Harri "Haba" Suomalainen) writes:
>In article <DAC.93Apr8150723@locust.frc.ri.cmu.edu> dac@frc.ri.cmu.edu (Daniel Christian) writes:
>
>   Could you get in touch with me?  We need an inexpensive (compared to a
>   laser rangefinder), eye safe distance measuring system.
>
>How do the laser range finders work? Could one be built "easily" from
>surplus lasers? (Half joking, half serious..)
>--
>--
>Harri Suomalainen        Harri.Suomalainen@hut.fi       haba@vipunen.hut.fi

The laser rangefinder I saw on one project worked by bouncing a laser light
pulse off the target being ranged, and measuring round-trip time.  This 
requires a pretty narrow pulse, which in turn requires a pretty high
pulse power.  For eye-safe, this one was an infrared (CO2) laser, and it
was purpose-built.

Unless you have a suitable pulsed IR laser handy, with a suitable pulse
width, you probably don't want to try it.
